Treatment of Radix Dipsaci extract prevents long bone loss induced by modeled microgravity in hindlimb unloading rats.

CONTEXT: Radix Dipsaci is a kidney tonifying herbal medicine with a long history of safe use for treatment of bone fractures and joint diseases in China. Previous studies have shown that Radix Dipsaci extract (RDE) could prevent bone loss in ovariectomized rats. OBJECTIVE: This study investigates the effect of RDE against bone loss induced by simulated microgravity. MATERIALS AND METHODS: A hindlimb unloading rat model was established to determine the effect of RDE on bone mineral density and bone microarchitecture. Twenty-four male Sprague-Dawley rats were divided into four groups (n = 6 per group): control (CON), hindlimb unloading with vehicle (HLU), hindlimb unloading treated with alendronate (HLU-ALN, 2.0 mg/kg/d), and hindlimb unloading treated with RDE (HLU-RDE, 500 mg/kg/d). RDE or ALN was administrated orally for 4 weeks. RESULTS: Treatment with RDE had a positive effect on mechanical strength, BMD, BMC, bone turnover markers, and the changes in urinary calcium and phosphorus excretion. MicroCT analysis showed that RDE significantly prevented the reduction of the bone volume fraction, connectivity density, trabecular number, thickness, tissue mineral density, and tissue mineral content as well as improved the trabecular separation and structure model index. DISCUSSION AND CONCLUSION: RDE was demonstrated to prevent the loss of bone mass induced by HLU treatment, which suggests the potential application of RDE in the treatment of microgravity-induced bone loss.

Synthesis, crystal structure and anti-fatigue effects of some benzamide derivatives.

A series of benzamide derivatives such as 1-(1,3-benzodioxol-5-ylcarbonyl) piperidine (1-BCP) were synthesized by the reaction of substituted benzoic acids with piperidine, morpholine or pyrrolidine using a novel method. The crystals of these benzamide derivatives were obtained by recrystallization. Structures of target and intermediate compounds were determined via FT-IR, 1H-NMR and elemental analysis and X-ray crystallography of select examples. The crystal structures of these compounds have potential applications to identify the binding site for allosteric modulators of the α-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA) receptor. The anti-fatigue effects of the benzamide derivatives in weight-loaded forced swimming mice were investigated in a swimming endurance capacity test used as an indicator of fatigue. The swimming times to exhaustion were longer in the b3, d3, and e3 groups than in the caffeine group (p<0.05). In conclusion, b3, d3 and e3 enhanced the forced swimming capacity of mice. The mechanism of the anti-fatigue effects will be studied in the future.

1-(1,3-Benzodioxol-5-yl-carbo-nyl) piperidine, a modulator of α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptor, ameliorates exercise-induced fatigue in mice.

The current study was designed to investigate the effects of 1-(1,3-benzodioxol-5-yl-carbonyl) piperidine (1-BCP) on swimming endurance capacity which as one indicator of fatigue in the weight-loaded forced swimming mice. Mice were given either vehicle or 1-BCP (0.1, or 0.2 mmol/kg body weight daily) by intraperitoneal injection once daily for 2 weeks. The 1-BCP groups showed a significant increase in swimming time to exhaustion compared with the control group. 1-BCP increased the liver glycogen (LG) and muscle glycogen (MG) contents significantly, while decreased the lactic acid (LA) and blood urea nitrogen (BUN) levels notably compared with control group. Besides, 1-BCP treatment also significantly improved the endogenous cellular antioxidant enzymes in mice by increasing the activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px). Therefore, this study demonstrated for the first time that the supplementation of 1-BCP, as a positive allosteric modulator of α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) receptor, could enhance the endurance capacity of mice and facilitated them recovery from fatigue. Thus, we provide a new effective therapeutic strategy for fatigue.